During the Cuban missile crisis of 1962, Acting U.N. Secretary-General U Thant sent a letter to Soviet Premier Khrushchev asking that he halt the Soviet ships then headed for Cuba in defiance of a U.S. quarantine. U Thant's request gave Khrushchev a plausible—and honorable— explanation for preventing an impending clash, and he accepted it. As Richard Walton states in his Cold War and Counterrevolution: The Foreign Policy of John F. Kennedy: "The Acting Secretary General [was] responsible for the breathing space that avoided confrontation at sea—and possible escalation into nuclear war."